为什么80%的码农都做不了架构师？>>> 
KVM支持在线扩展磁盘空间，支持RHEL系列6以上的版本
列出在线虚拟机磁盘
[root@e3 images]# virsh list --all
Id 名称 状态
----------------------------------------------------
29 centos6.6 running
41 centos6.5 running
- kvm001 关闭
- kvm002 关闭
- kvm003 关闭
- template 关闭
[root@e3 images]# virsh domblklist centos6.5 #列出在线虚拟机磁盘情况
目标 源
------------------------------------------------
vda /data/kvm/images/centos6.5.qcow2
[root@e3 images]#创建一块qcow2磁盘并在线添加
[root@e3 images]# qemu-img create -f qcow2 centos6.5-add.qcow2 5G #创建一块5G大小的硬盘
Formatting 'centos6.5-add.qcow2', fmt=qcow2 size=5368709120 encryption=off cluster_size=65536 lazy_refcounts=off
[root@e3 images]# ll centos6.5-add.qcow2
-rw-r--r--. 1 root root 197120 1月 21 18:31 centos6.5-add.qcow2
#在线添加磁盘
[root@e3 images]# virsh attach-disk centos6.5 /data/kvm/images/centos6.5-add.qcow2 vdb --cache=none --subdriver=qcow2 ##
成功附加磁盘查看
[root@e3 images]# virsh domblklist centos6.5
目标 源
------------------------------------------------
vda /data/kvm/images/centos6.5.qcow2
vdb /data/kvm/images/centos6.5-add.qcow2 #添加成功
#切换虚拟机里查看
[root@kvm003 ~]# fdisk -l
Disk /dev/vda: 32.2 GB, 32212254720 bytes
16 heads, 63 sectors/track, 62415 cylinders
Units = cylinders of 1008 * 512 = 516096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000903e2
Device Boot Start End Blocks Id System
/dev/vda1 * 3 1018 512000 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/vda2 1018 41611 20458496 8e Linux LVM
Partition 2 does not end on cylinder boundary.
Disk /dev/mapper/VolGroup-lv_root: 19.9 GB, 19906166784 bytes
255 heads, 63 sectors/track, 2420 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/mapper/VolGroup-lv_swap: 1040 MB, 1040187392 bytes
255 heads, 63 sectors/track, 126 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/vdb: 5368 MB, 5368709120 bytes #添加的
16 heads, 63 sectors/track, 10402 cylinders
Units = cylinders of 1008 * 512 = 516096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000